1. Key Laboratory of Earthquake Geodesy, Institute of Seismology, China Earthquake Administration, Wuhan 430071, China
2. Gravitation and Earth Tide, National Observation and Research Station, Wuhan 430071, China
3. School of Architecture and Civil Engineering, Chengdu University, Chengdu 610106, China
4. College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
5. Department of Surveying Engineering, School of Civil and Transportation, Guangdong University of Technology, Guangzhou 510006, China